81, 27, 9, find the common ratio of the given sequence, and write an exponential function which represents the sequence. use n = 1, 2, 3, a) 3; f(n) = 81^n-1 b) 3; f(n) = 81(3^)n-1 c) 1/3; f(n)=81(3)^n-1 d) 1/3; f(n)=81(1/3)^n-1

Evaluate cos2θ for cosθ = square root of 3/2

Estimate the area under the curve f(x) = 16 - x^2 from x = 0 to x = 3 by using three inscribed (under the curve) rectangles. answer to the nearest integer.

Given: ae ≅ ce ; de ≅ be prove: abcd is a parallelogram. we have that ab || dc. by a similar argument used to prove that △aeb ≅ △ced, we can show that △ ≅ △ceb by. so, ∠cad ≅ ∠ by cpctc. therefore, ad || bc by the converse of the theorem. since both pair of opposite sides are parallel, quadrilateral abcd is a parallelogram.